Chances are that whichever way OP goes, LGA115x and DDR4 will be pretty much end-of-life too by the time he wants an upgrade anyway since Intel breaks backward-compatibility every other year. As Supa already pointed out, every CPU likely to ever fit in current Intel motherboards has already launched, better off buying the CPU you intend to bury the motherboard with than buying twice, especially considering how slowly Intel's higher-end CPU prices drop even on the used market.Another factor to consider is upgrade path. The 4790k doesn’t have one due to using end of life socket and RAM.
Yeah so let's take this one step at a time the i7-4790k is already the top CPU for it's platform so there is nowhere else to go unless you get a new platform,the i3-8350k is in the middle of the stack, you can go to the 9900k on the same platform this is an upgrade path and a huge one at that.Chances are that whichever way OP goes, LGA115x and DDR4 will be pretty much end-of-life too by the time he wants an upgrade anyway since Intel breaks backward-compatibility every other year. As Supa already pointed out, every CPU likely to ever fit in current Intel motherboards has already launched, better off buying the CPU you intend to bury the motherboard with than buying twice, especially considering how slowly Intel's higher-end CPU prices drop even on the used market.